Wind power, biofuels, and even nukes seem to be dominating the talk about energy sources that should help reduce greenhouse gas emissions. Lost in the discussion is the possibility that ol' coal can go some way towards providing clean power using the process of underground coal gasification (UCG). This technology is particularly salient here in the UK with its large, untapped coal supplies. With the high costs of importing fuel from abroad--both economic and political--UCG is gaining a serious look. Consulting firms, energy industry, and academic institutions have already teamed up to form a UCG partnership. A whole raft of advantages are touted below that obtain from coal being utilized in situ (on site), such as avoiding transportation and storage as well as possible mining disasters [have you seen my wife, Mr. Jones?] Coupled with carbon sequestration technologies that store carbon dioxide emissions underground, the future may once more belong to the fuel that has been a large factor behind global warming. The redemption of coal, coming to an energy station near you, perhaps:· Lower fugitive dust, noise and visual impact on the surface
· Lower water consumption
· Low risk of surface water pollution
· Reduced methane emissions
· No dirt handling and disposal at mine sites
· No coal washing and fines disposal at mine sites
· No ash handling and disposal at power station sites
· No coal stocking and transport
· Smaller surface footprints at power stations
· No minewater recovery and significant surface hazard liabilities on abandonment.
Additional benefits are:
· Health and safety
· Potentially lower overall capital and operating costs
· Flexibility of access to mineral
· Larger coal resource exploitable
The Times of London has more on the potential rebirth of coal and its possible uses:
Coal. The very same filthy fossil fuel, dirtiest of them all, that powered the industrial revolution and let global warming out of its cage. The very same that rotted miners’ lungs, blotted out the sun and choked London with smog. The very same that still generates a third of the UK’s electricity and which David Kerr describes, for all the above reasons, as an “undesirable trend”. And yet coal has a lot going for it. The domestic industry may have been Thatchered into the ground, and 80% of our supplies may now be imported, but coal worldwide is plentiful and can be sourced from countries in Europe and the Americas which are far better disposed towards us than the gas merchants of the East.But nobody wants to fill the air with smoke. Atmospheric pollution was a public enemy long before climate change became an issue, and there can be no going back to it. If coal is to resume its historic role, then it will have to clean up its act. And this is exactly what Golby and others propose. “Clean coal technology” (CCT) is not an oxymoron. Various processes that can be summarised as “carbon capture and storage” (CCS) have been designed to do exactly what the name suggests – remove or intercept CO2 from coal and store it deep underground. It can be done before combustion by a gasification process, or afterwards by stripping carbon from flue gas. The efficacy of the technique has been shown in small-scale trials, but high development costs are holding it back commercially and it’s not something “the market” can afford to deliver.
Yet Golby, head of Britain’s biggest gas and electricity company, is unequivocal: “I believe that this is one of the really critical technologies,” he says. “Unless we can solve the problem of coal, we are going to lose the climate-change battle.” It is a problem that extends far beyond the UK’s ability to power itself sustainably. China and India are going to burn coal – more and more of it – come what may, and unless a way can be found to cut their carbon emissions, and those of every other coal-burning economy, nothing we do in Britain is going significantly to impede humanity’s march to self-immolation. “It will require an international effort not dissimilar to the US putting a man on the moon,” says Golby. “It will take tens of billions of pounds. Some of it will come from industry. Some will have to come from governments...”For many others, the principal lunacy of the UK’s position is not that it ignores the potential for clean energy from imported coal, but rather that it ignores the wealth under its own feet. Accounts vary. One expert tells me that 75% of the coal that ever existed in the UK still lies undisturbed – a buried mountain of pent-up energy that could fuel the country for centuries. Another says the likelier figure is 98%. Either way, it’s a lot of coal. The problem, of course, is getting at it. If it was easily accessible, then the whole energy equation might look rather different. Coal would still be king, and CCS would be a no-brainer.
But there is a powerful body of opinion that says not only that much of it is accessible, but that it can be extracted with minimum environmental impact – ie, without open-cast mining – and with great benefit to national security and the carbon economy. The key to it is “underground coal gasification” (UCG), a technique devised by the Scottish chemist Sir William Ramsay. The Coal Authority thumbnails it as “a method of converting unworked coal deep underground into a combustible gas”, which, through CCS, contains no CO2. The result is “clean energy with minimal greenhouse emissions”...
This seems no less extraordinary to energy professionals than it does to laymen. “The government should be putting a big push at getting gasification technology on the road,” says the ICE’s David Kerr. “It’s the most promising technology currently available,” says Graham Chapman, managing director of the energy consultant Energy Edge. Since 2005, the campaign to promote UCG, both in the UK and worldwide, has been led by the UCG Partnership, an independent organisation in Woking, Surrey, whose members include oil and gas companies, banks, regional development agencies, universities and governments.
One of its two founding directors, Rohan Courtney, quotes the British Geological Survey, which concluded that UCG could unlock an extra 17 billion tonnes of indigenous coal – enough for another 300 years at current rates of consumption. (Compare this with the range of 200m to 2,000m tonnes estimated for “mineable” reserves). Like a schoolmaster delivering a favourite lesson, Courtney runs through the advantages at dictation speed. UCG does not suffer from the same negative public image as coal mining. It does not endanger lives underground; does not ruin the countryside; does not involve high transport and labour costs. Production, too, would cost less than either mining coal or buying oil and gas from elsewhere. We would have security of supply.
“We own the coal,” says Courtney. “We would not be subject to market forces on the price of importing energy, high transport costs and the political risks of purchasing oil, gas or coal from a country with a different agenda.” Instead of importing, we could export the technology. Best of all, with directional drilling, UCG can be used under the sea. Rich seams lie under the Firth of Forth and southern North Sea – at least five billion tonnes, and possibly much more.
